In the conventional liquid manure system, liquid manure in the form of a slurry, is stored in a reservoir and periodically it is pumped from the reservoir to a spreader tank which is drawn by a tractor. In some cases the liquid manure in the tank is spread over the ground surface by a spray device while in other cases, the liquid manure is discharged from the spreader tank adjacent a series of plow elements, or soil penetration elements, which penetrate the soil so that the liquid manure is discharged beneath grade.
U.S. Pat. No. 3,793,967 shows an apparatus for distributing liquid manure beneath grade level, and in that patent a rigid, hollow frame is mounted on the three-point hitch of the tractor and plow elements or soil penetrators are connected to the lower ends of the frame. The liquid manure is conducted through a flexible tube to the hollow frame and discharged behind the plow elements.